Sangnaimueang, Siriphon, and Karuna Cherdjirapong. 2022. “Guidelines for Developing Public Relations Efficiency of Nakhon Ratchasima Municipality, Nakhon Ratchasima Province”. Journal of Research and Development Institute Rajabhat Maha Sarakham University 9 (1):225-42. https://so03.tci-thaijo.org/index.php/rdirmu/article/view/254671.